激励源(泵浦源)向激光物质提供能量,使激光物质处于平衡状态,形成粒子数反转。( )
参考答案:错
—"Does he like apples?"
—"_______".[ ]
A. Yes, he does
B. Yes, he is
C. No, he isn't
D. No, he does
宜用麸炒法炮制的药物有()
A、苍术
B、枳壳
C、山药
D、白术
E、僵蚕